It's probably too late now. Too bad you did not think ahead when they were an inch in diameter. I think you have to cut out one or t'other.

Would a piece of an old garden hose cut to size work? I have done that with some of my trees before with success.

Do you have anything to tie the offending trunk to? I tied 2 trunks together for a year with a hard rubber tie-down strap on a dogwood for a similar situation to re-train the direction. After that time I untied them and they aren't rubbing anymore, and actually look better. Didn't have to cut anything either.

you MIGHT take a cinder block with holes... and some stout rope ... and tie the rope to the lower branch ... and the other to the cinder block ... pulling down the lower branch ...

or two blocks if the tree resists ... or three ...

i have seen the method in books about Japanese gardens and how they train maples ....

it might not be the best look for the front of the house .... as it might have to be there for a few years ...

maybe google images will find you a picture .... ken

How about scraping off the outer bark where the two branches touch each other, then bind the branches firmly together with grafting tape. After a year, remove the grafting tape, and (with any luck!) the branches will be grafted onto each other with a solid wood bond.

Resin

Thanks for the brainstorming! I'll take a look at the tree to see if the pulling apart method would work. The grafting idea is interesting, but I'm too much of a chicken to try it ;)

Smallmouth, the rubber garden hose seems like a simple, good idea. On the trees where you tried this, did the hose rub the bark raw at all?

How about using that black foam insulation used on your AC refrigerant lines? Looks like this: http://www.aeroflexusa.com/images/secondary/pa2.jpg

The branches I'm trying to isolate are about 1" wide. This stuff would fit perfectly. I'm just wondering if it would promote fungus or disease growth or would interfere with bark growth. What do you think?

Any thoughts on the foam?

I want to know about the foam also. We just moved to a 115 y o house so all the trees are established ….I have a giant live oak limb rubbing up against another large limb from a different tree …HELP what can I do ??

Please hire a certified arborist to make a site visit and evaluate your valuable trees.